Recently I've watched a bit of Killing Eve which i didn't like at all, Line of Duty which has steadily gone downhill after being really good for a while, Dr. Who which is utterly dreadful, a few others that were so bad I can't remember them (this is my general impression, I try to watch something and end up immediately hating it), the bodyguard which i found boring and predictable. I'm not really into period drama but I hear the BBC do good things in that area, but its not my thing. In general, I find their dramas to be very unartistic and formulaic.
IMO the best thing to come out of the BBC in recent years was Orphan Black and that was BBC America and finished a good few years ago now.
TBH the documentaries I watch are mostly science and history documentaries, and I think they're great, although even the science docs have dried up somewhat in the last couple of years. Horizon used to be awesome, even just 3-4 years ago, but they stopped talking about pure science and moved to a kind of health and lifestyle (ie more fearmongering and 'headline-y' science) focus. Also, Storyville is of inconsistent quality but the good ones are really great. I haven't noticed a particular problem with celebrity.
I'm a particular fan of Bettany Hughes' documentaries:
https://www.bbc.co.uk/iplayer/episodes/b06542cg/genius-of-the-ancient-world